Light Diffusing Member For Transmission Screen

Abstract

There is provided a light diffusing member for use in a transmission screen, which has an excellent surface protective effect while maintaining an antireflection effect. The light diffusing member for use in a transmission screen comprises a hard coat layer provided on a surface of a substrate having a single or multilayer structure. The substrate contains fine particles, and the surface gloss of the hard coat layer as measured under conditions of incident angle 60° / reflection angle 60° is 60 to 80 by supposing the surface gloss of a gloss standard plate to be 100.

Description

TECHNICAL FIELD [0001] This invention relates to a light diffusing member for use in transmission screens used, for example, in transmission projection televisions, and an optical member and a transmission screen using the light diffusing member. BACKGROUND ART [0002] Transmission projection televisions are display devices for enlarging and projecting images from light sources such as CRTs, liquid crystal projectors, and DLPs onto transmission screens. In such display devices, in order to reduce dazzling when a screen is viewed, for example, light diffusing plates and the like for diffusing outgoing light are provided on a screen surface. Further, in order to reduce a deterioration in visibility of projected images caused by reflection of external light from the screen surface, an antireflection film is sometimes provided on the screen surface. For example, as disclosed in Japanese Patent Laid-Open No. 295818 / 1999 and Japanese Patent Laid-Open No. 28169 / 1995, the light diffusing pla...

AI Technical Summary

Benefits of technology

[0005] The present inventors have now found that, in the provision of a hard coat layer on a light diffusing plate, the surface hardness and surface gloss of the hard coat layer can be regulated bhoy regulating the particle diameter and content of the fine particles contained in the substrate and the thickness of the resin constituting the hard coat layer, and, consequently, a light diffusing member having a satisfactory surface protective effect can be realized while maintaining the antireflection effect. The present invention has been made based on such finding.

[0006] Accordingly, an object of the present invention is to provide a light diffusing member for use in transmission screens, which simultaneously has antireflection effect and excellent surface protective effect.

[0007] The above object of the present invention can be attained by a light diffusing member for a transmission screen, comprising: a substrate having a single or multilayer structure; and a hard coat layer provided on a surface of the substrate, wherein the substrate contains fine particles, and the surface gloss of the hard coat layer as measured under conditions of incident angle 60° / reflection angle 60° is 60 to 80 by supposing the surface gloss of a gloss standard plate to be 100. In a preferred embodiment, the hard coat layer has a surface hardness of 3 H or more as measured by a pencil hardness test according to JIS K 5600-5-4. The provision of a hard coat layer having the above surface hardness on a viewer side (outermost surface) can realize satisfactory surface protective effect while maintaining antireflection effect.

Problems solved by technology

The provision of a protective layer (also referred to as “hard coat layer”) on the surface of the light diffusing plate for screen surface protection purposes, however, poses a problem that the concaves and convexes on the light diffusing plate surface disappear and, consequently, the antireflection effect cannot be attained.

On the other hand, when the provision of the protective layer satisfactory for attaining the antireflection effect is contemplated, however, the thickness of the protective layer should be smaller than the level of the concaves and convexes on the surface of a light diffusing plate, that is, the particle diameter of the transparent fine particles, and, consequently, disadvantageously, a satisfactory surface protective effect cannot be attained.

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